Synthesis of optically active arylaziridines by regio- and stereospecific lithiation of N-bus-phenylaziridine

(Chemical Equation Presented) α,α-Disubstituted aziridines can be produced in good yields by selective lithiation of W-fert-butylsulfonyl-2- phenylaziridine (n-BuLi/TMEDA, Et2O) at the benzylic position and subsequent trapping with a range of electrophiles. Repetition of the lithiation/electrophilic trapping sequence provides a stereocontrolled route to trisubstituted aziridines. Using (R)-N-tert-butylsulfonyl-2-phenylaziridine, the α,α-disubstituted aziridines can be produced as single enantiomers (er >98:2), indicating that the intermediate organolithium is configurationally stable. Efficient aziridine ring-opening reactions leading to 1,2-diamines and 1,4-diamines are also reported. © 2009 American Chemical Society.